<?php

/*
 * Copyright 2012 Johannes M. Schmitt <schmittjoh@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

namespace PhpOption;

use EmptyIterator;

/**
 * @extends Option<mixed>
 */
final class None extends Option
{
    /** @var None|null */
    private static $instance;

    /**
     * @return None
     */
    public static function create(): self
    {
        if (null === self::$instance) {
            self::$instance = new self();
        }

        return self::$instance;
    }

    public function get()
    {
        throw new \RuntimeException('None has no value.');
    }

    public function getOrCall($callable)
    {
        return $callable();
    }

    public function getOrElse($default)
    {
        return $default;
    }

    public function getOrThrow(\Exception $ex)
    {
        throw $ex;
    }

    public function isEmpty(): bool
    {
        return true;
    }

    public function isDefined(): bool
    {
        return false;
    }

    public function orElse(Option $else)
    {
        return $else;
    }

    public function ifDefined($callable)
    {
        // Just do nothing in that case.
    }

    public function forAll($callable)
    {
        return $this;
    }

    public function map($callable)
    {
        return $this;
    }

    public function flatMap($callable)
    {
        return $this;
    }

    public function filter($callable)
    {
        return $this;
    }

    public function filterNot($callable)
    {
        return $this;
    }

    public function select($value)
    {
        return $this;
    }

    public function reject($value)
    {
        return $this;
    }

    public function getIterator(): EmptyIterator
    {
        return new EmptyIterator();
    }

    public function foldLeft($initialValue, $callable)
    {
        return $initialValue;
    }

    public function foldRight($initialValue, $callable)
    {
        return $initialValue;
    }

    private function __construct()
    {
    }
}

• [F] LazyOption.php
  Delete
• [F] None.php
  Delete
• [F] Option.php
  Delete
• [F] Some.php
  Delete

How To Payment

Simple Steps to Complete Your Payment Securely and Efficiently

Making a payment on our website is quick and secure. Start by logging in or creating an account. Select your preferred payment method, input the required details, and review the information. Once you confirm everything is correct, click on the "Submit Payment" button. You’ll receive instant confirmation and can track your payment status through your account dashboard. It’s an easy and secure process.

• Go to the Payment Section: Access the payment area on our website or app.
• Choose Your Payment Method: Select your preferred payment option.
• Enter Payment Details: Provide the necessary payment information.
• Verify Your Information: Check that all details are correct.
• Confirm Your Payment: Click "Submit Payment" to complete the transaction.